Definition of "adversarial"

adversarial

/ˌæd.vəˈsɛə.ɹi.əl/

adjective
comparative more adversarial, superlative most adversarial
1. Characteristic of, or in the manner of, an adversary; combative, hostile, opposed.
  Quotations
  In polling by the Pew Research Center in November 2008, fully half the respondents thought the two parties would cooperate more in the coming year, versus only 36 percent who thought the climate would grow more adversarial.
  2012 November 7, Matt Bai, “Winning a Second Term, Obama Will Confront Familiar Headwinds”, in New York Times‎
  The White Paper therefore aims to tackle complexity rather then ownership of the railways, and to eliminate "the adversarial relationships between operators, suppliers, NR and government".
  2021 June 2, “Network News: Simplification, not nationalisation”, in RAIL, number 932, page 9
2. (law) In which issues are tried through the presentation of evidence and argument by adverse parties, with no or limited inquiry by the court's own initiative.